In an article storage facility as described above, the control portion causes the movement mechanism to execute a movement operation of moving the movement support body to a target stop position that is set so as to correspond to each of the plurality of storage sections and stopping the movement support body at the target stop position, and a transfer operation of lowering the movement support body at the target stop position and delivering the article to the storage support body. The target stop position needs to be set at a proper position that is a position of the movement support body at which the article supported by the movement support body can be delivered to a proper storage position of the storage support body by the transfer operation. However, the positions of the storage support bodies of the plurality of storage sections will be slightly shifted from the design positions due to an installation error occurring during installation of the facility. Accordingly, even when a movement support body is located at the target stop position that is provided by design, the movement support body may not be located at a proper position relative to the actually installed storage support body.
For this reason, for example, JP 2010-83593A (Patent Document 1) discloses a technique for attaching a target mark at a specific location of the storage support body of each storage section, imaging the target mark from the front side of the storage section with a pair of imaging devices supported by the movement support body in an orientation in which their imaging directions intersect each other, calculating, based on two images of the imaged target mark, the positional offset amount in the vertical direction and the positional offset amount in the lateral direction, and the front-rear direction between the movement support body and the storage support body, and correcting the target stop position based on the positional offset amounts.
However, the technique disclosed by Patent Document 1 corrects the position of the storage support body based on the positions of the target mark in the images captured from the front side of the storage section, and thus has the following problem.
That is, due to the constraint that the target mark must be provided at such a position that supporting of an article by the storage support body will not be obstructed, the set position of the target mark must be a position away from a position of the storage support body at which the article is supported. Accordingly, it is not possible to directly measure the position of the article supporting portion of the actually attached storage support body, and there is the possibility that the corrected target stop position may be shifted from the proper position relative to the storage support body.
In particular, even if the orientation of the actually installed storage support body in plan view is an offset orientation shifted from the design orientation, when that offset is an offset in the rotational direction about the target mark in plan view, the offset amount in this plan view orientation will not be reflected on the position of the target mark. Accordingly, no matter how accurately the position of the target mark of the actually attached storage support body can be measured, when the plan view orientation of the storage support body is shifted from the design orientation, it is not possible to know the position of the article supporting portion of the storage support body, making it impossible to appropriately correct the target stop position.
Moreover, since all of the images captured from different imaging directions in Patent Document 1 are images resulting from imaging the target mark from the front side of the storage section, the position of the target mark in the front-rear direction cannot be measured as accurately as the positions in the lateral direction and the vertical direction. Accordingly, in the case of measuring the positional offsets in the lateral direction, the vertical direction, and the front-rear direction from the proper position when the movement support body is located at the target stop position, the positional offsets in the lateral direction and the vertical direction can be accurately calculated, but the positional offset in the front-rear direction cannot be calculated as accurately as the positional offsets in the lateral direction and the vertical direction. Consequently, the target stop position cannot be corrected to a proper position in the front-rear direction.
Meanwhile, JP 2001-225909A (Patent Document 2) describes a technique for measuring proper positions in the lateral direction and the front-rear direction relative to a storage support body that is actually supporting an article. According to the technique described in Patent Document 2, the proper positions of the movement support body in the lateral direction and the front-rear direction are acquired by attaching a jig plate having a target mark attached thereto to a storage support body in a state in which the position relative to the storage support body in plan view is constant, and detecting the target mark with a detection device provided in the movement support body.
In Patent Document 2, in the case of acquiring the target stop positions for the lateral direction and the front-rear direction, the jig plate is attached to a proper storage position of the storage support body for which the target position is to be acquired, and the target mark attached to the jig plate is detected with the detection device mounted to the movement support body, and thereby, the positions in the lateral direction and the front-rear direction from among the target stop positions of the movement support body are acquired.